Electric switch contactor

摘要

The contactor is provided in a housing (1), and has a main current loop with one or more movable contacts (4) and terminal clamps for the main current loop. The arrangement also includes an electromagnetic drive (5, 6) with a mechanism (9) actuated by a movable armature of the drive. The mechanism (9) is provided between the drive and the movable contact(s) (4) to actuate them when the drive is supplied with current by transmission of a main signal, and opens them again when no current flows. A control loop powers the electromagnetic drive (5, 6). A low resistance (7) is normally short circuited by a movable auxiliary contact (8) and is connected in series with the electromagnetic drive (5, 6) when the auxiliary contact is actuated. A switch (18) can be manually set to an automatic operation position where the main contacts are actuated by a main signal and are released again at the end of the signal. The switch (18) can also be set to a forced operation position where it manually puts the mechanism back to the actuation position of the main contacts (4) and holds it there. Under the effect of a control signal when the switch (18) is in the force operation position actuation of the electromagnetic drive causes actuation of the auxiliary contacts (8) to set the resistance (7) in series with the electromagnetic drive and to trigger the control switch (18) which is set back to the automatic operation position. The main contact mechanism (9) is arranged such that it is directly actuated by the control switch (18) when it is in the force operation position while the armature of the electromagnetic drive is scarcely or not at all affected by the switch when it is in this position.